i picked up a 20W 24" coralife 50/50 bulb for my 37 gal. i paid $10 more than if i would have ordered it online.. i just wanted it! anyway.. im disappointed, it's not as "color enhancing" as I thought it would be , and I think that the main reason for that is: 20W - 37 gal - just not enough juice... I would imagine it being a bit better on a 29gal ... also, I have peat tanning the water , so the yellowish water + the hint of blue from the bulb = makes the tank green! ha! oh well I guess I'll try to bring it back. or maybe someone wants it???